Such a great results.. great tips.. by a great teacher
My hat's off to you
Cherry and friend (fruit fly -- Rhagoletis indifferens)
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Yousef Alhabshi
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rjlittlefield
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NikonUser, I followed up by getting some of that liquid Anbesol with 20% benzocaine. I haven't tried it on fruit fly larvae yet -- those were all gone by when the Anbesol came. But I did try adding some to plain water, just to see what would happen. That was very informative. The mixture simmered for a while, and when it settled down, there were big chunks of waxy stuff floating in water. When I checked solubility, I found that benzocaine is only "sparingly soluble in water" (says Wikipedia). As a number, NIH lists the solubility as 1310 mg/L (at 30 °C), which I translate to 0.13% w/w.That could certainly explain why a water solution of the stuff didn't accomplish much. It's very different from lidocaine, which is freely soluble in water. Next exercise: get some lidocaine and see what that does. (Added: in quick experiments, it seems that the liquid Anbesol will also dilute cleanly in some alcohol/water mixtures. Finding the optimum ratio could be another route forward.)
Christian, I'm glad those anterior spiracles caught somebody else's fancy. I didn't even know what those structures were, until I started looking at anatomy diagrams.
Yousef, 'tis written, "when the student is ready, the teacher will appear." I'm a great fan of your work also.
--Rik
Christian, I'm glad those anterior spiracles caught somebody else's fancy. I didn't even know what those structures were, until I started looking at anatomy diagrams.
Yousef, 'tis written, "when the student is ready, the teacher will appear." I'm a great fan of your work also.
--Rik
Rik,
Thank you for the great photos and demonstration.
Regarding immobilizing insects:
Dermoplast Blue also has 20% Benzocaine in a liquid mixture containing alcohol. You should spray that directly onto your subject, wait for numbing effect, then wipe it off. Then you can put your subject into water, if you have to. That original spray mixture has the perfect alcohol and surfactant percentage to keep benzocaine soluable. Once you dilute that original mixture, solvent ratio changes and things will precipitate like what you have seen. Also original spray is formulated to be quickly absorbed by human skin (which may be close to a maggot's skin), water dilution reduces that absorption.
Solarcaine burn relief spray (which Walgreen sells) has 0.5% lidocaine in it. But again, I suggest using it without dilution. Let your subject be numbed by it first, then put subject in water if you have to. This lidocaine should work for pond protists too, though some dilution in water may be needed for those much smaller critters. Graham Matthews uses lidocaine: http://www.micromagus.net/index_micro.html
Thank you for the great photos and demonstration.
Regarding immobilizing insects:
Dermoplast Blue also has 20% Benzocaine in a liquid mixture containing alcohol. You should spray that directly onto your subject, wait for numbing effect, then wipe it off. Then you can put your subject into water, if you have to. That original spray mixture has the perfect alcohol and surfactant percentage to keep benzocaine soluable. Once you dilute that original mixture, solvent ratio changes and things will precipitate like what you have seen. Also original spray is formulated to be quickly absorbed by human skin (which may be close to a maggot's skin), water dilution reduces that absorption.
Solarcaine burn relief spray (which Walgreen sells) has 0.5% lidocaine in it. But again, I suggest using it without dilution. Let your subject be numbed by it first, then put subject in water if you have to. This lidocaine should work for pond protists too, though some dilution in water may be needed for those much smaller critters. Graham Matthews uses lidocaine: http://www.micromagus.net/index_micro.html
Selling my Canon FD 200mm F/2.8 lens
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rjlittlefield
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Thank you for the additional suggestions about anesthetics.
I did consider Solarcaine "First Aid Medicated Spray", but the can I have says 20% benzocaine. I stopped that line of investigation when I first sprayed it on a glass slide and observed that it formed an orange-peel texture, followed by waxy lumps when water was added. That didn't seem at all the sort of stuff that I wanted to get on a subject I was intending to photograph.
Checking now to see what else is available, I see that Solarcaine has a different product they call "Cool Aloe Burn Relief", which indeed is 0.5% lidocaine, plus "aloe barbadensis leaf juice, water, propylene glycol, glycerin, triethanolamine, isopropyl alcohol (0.06% v/v), polysorbate 80, carbomer, diazolidinyl urea, menthol, disodium EDTA, yellow 5, blue 1". That might work better, since at least all that stuff looks to be water soluble.
However, I opted instead to get a small vial of 2% injectable lidocaine from my vet. I haven't had an opportunity yet to use it on fruit fly larvae, but it worked a treat on the 5 mm and 12 mm bloodworms that I just now tested. Apparently complete immobilization in seconds, no obvious change in the appearance of tissues.
--Rik
I did consider Solarcaine "First Aid Medicated Spray", but the can I have says 20% benzocaine. I stopped that line of investigation when I first sprayed it on a glass slide and observed that it formed an orange-peel texture, followed by waxy lumps when water was added. That didn't seem at all the sort of stuff that I wanted to get on a subject I was intending to photograph.
Checking now to see what else is available, I see that Solarcaine has a different product they call "Cool Aloe Burn Relief", which indeed is 0.5% lidocaine, plus "aloe barbadensis leaf juice, water, propylene glycol, glycerin, triethanolamine, isopropyl alcohol (0.06% v/v), polysorbate 80, carbomer, diazolidinyl urea, menthol, disodium EDTA, yellow 5, blue 1". That might work better, since at least all that stuff looks to be water soluble.
However, I opted instead to get a small vial of 2% injectable lidocaine from my vet. I haven't had an opportunity yet to use it on fruit fly larvae, but it worked a treat on the 5 mm and 12 mm bloodworms that I just now tested. Apparently complete immobilization in seconds, no obvious change in the appearance of tissues.
--Rik
^ Rx strength lidocaine is of course even better. I did not know you can get it so easily (which was why I suggested the OTC version). 1%- 2% strength can be used for epidural (giving birth) too. A worm may not even need that much. It works very well on pond protists too.
Selling my Canon FD 200mm F/2.8 lens
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rjlittlefield
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Thanks, guys. This was a fun project.
Abpho, the explanation for my absence on the front page is that until recently the administrators have had a self-imposed restriction that we weren't eligible for our own Appreciation Awards. Of course that's where the front page images come from. I've been an administrator since 2006, so to have seen me on the front page before now, you would need to have been around for quite a while! But times change, and we quietly broke with tradition last October by selecting Laurie Knight's live stacked aphid.
By the way, I thank my fellow administrators for nominating this thread in the first place, and then overriding my suggestions that perhaps another image would serve better on the front page. I personally find those fangs to be a little fearsome, especially since I know that I inevitably swallow some of these critters!
--Rik
Abpho, the explanation for my absence on the front page is that until recently the administrators have had a self-imposed restriction that we weren't eligible for our own Appreciation Awards. Of course that's where the front page images come from. I've been an administrator since 2006, so to have seen me on the front page before now, you would need to have been around for quite a while! But times change, and we quietly broke with tradition last October by selecting Laurie Knight's live stacked aphid.
By the way, I thank my fellow administrators for nominating this thread in the first place, and then overriding my suggestions that perhaps another image would serve better on the front page. I personally find those fangs to be a little fearsome, especially since I know that I inevitably swallow some of these critters!
--Rik